We aimed to determine the prevalence of drug and polydrug use in people living with HIV in Austria for the first time for which a two center cross-sectional study was performed. Participants were recruited from consecutive patients during their regularly scheduled visits. In total 438 participants were included in the analysis. For this study we used paper-pencil and online-based questionnaires. The prevalence of illicit drug use was 60.5%; with cannabis use at 31.5%, nitrates at 31.5%, sildenafil/tadalafil at 24% and cocaine at 14%, being the most used substances. Use of more than one substance (polydrug) in drug users was 69.4% or 42.0% in the total study population. Younger age, male gender, and living in an urban area were associated with drug use. Moreover, drug use during clubbing and sex, HIV therapy non-adherence and younger age were associated with polydrug use. Drug users reported condomless sex in 42.4% and performing sexual acts they would not do sober in 44.1%. Results indicate a high prevalence of illicit drug use in PLWHIV in Austria. New research focusing on illicit drug use in PLWHIV should focus on the use of substances during sex and surrounding practices.